Electrical assemblies, such as insulators and surge arresters, are typically enclosed within a weathershed housing for insulating and protecting the internal electrical components or core members from the outside environment. Insulators are extensively used to support the electrical conductors of electric power lines. Surge arresters, on the other hand, are commonly connected across electrical equipment to shunt over-voltage surges, such as lightning strikes. A problem common to both insulators and arresters is preventing water ingress at the interface between the end fittings and the ends of the weathershed housings. Specifically, water penetrates between the end fittings and the ends of the weathershed housing, thereby initiating electrical and mechanical destruction of the electrical assembly.
While many attempts have been made to overcome this problem, numerous disadvantages are present in these prior electrical assemblies. For example, many of the prior electrical assemblies have end fittings with an integral end collar which is crimped about the end portion of the weathershed housing. These types of end fittings often do not provide an effective seal, since after a certain number of temperature cycles, gaps appear. Other prior electrical assemblies have their weathershed housings axially compressed between the end fittings. However, these types of seals are vulnerable to breakdown because the electrical potential migrates over the atmospherically soiled weathershed housing, thereby causing the elastomeric housing to erode at its interfaces with the end fittings.
Examples of these prior electrical assemblies are disclosed in the following U.S. Patents: U.S. Pat. No. 974,177 to Noeggerath; U.S. Pat. No. 1,246,461 to Plimpton; U.S. Pat. No. 1,251,097 to Peck; U.S. Pat. No. 1,266,711 to Plimpton; U.S. Pat. No. 1,446,523 to Steinberger; U.S. Pat. No. 1,617,154 to Gouverneur; U.S. Pat. No. 1,738,188 to Lanyon; U.S. Pat. No. 3,898,372 to Kalb; U.S. Pat. No. 4,057,687 to Willem; U.S. Pat. No. 4,296,276 to Ishihara; U.S. Pat. No. 4,343,966 to Pargamin; U.S. Pat. No. 4,414,429 to Kaczerginski; U.S. Pat. No. 4,427,843 to Ishihara et al; U.S. Pat. No. 4,435,615 to Kaczerginski et al; and U.S. Pat. No. 4,604,498 to Kuhl.
Further examples of these prior electrical assemblies are disclosed in United Kingdom Patent 169,239, issued on Sep. 19, 1921; German Patent 456,051, issued on Feb. 13, 1928; German Patent 1,931,550, issued on Dec. 23, 1970; German Patent 2,611,504, issued on Sep. 29, 1977; and French Patent 2,424,613, issued on Dec. 28, 1979.
In view of the above, it is apparent that there exists a need to provide electrical assemblies with a sealing system for coupling and sealing the end fittings and the ends of the weathershed housing together in a weathertight manner. This invention addresses this need in the art along with other needs which will become apparent to those skilled in the art once given this disclosure.